Mass extinctions of land-dwelling animals occur in 27-million-year cycle

Posted: December 13, 2020 by oldbrew in Cycles, History, research, solar system dynamics, volcanos
Tags: ,

Model dinosaur

The lead author of the study puts the blame on “the largest cataclysmic impacts and massive volcanism, perhaps sometimes working in concert.” The study says: ‘The correlations and similar cycles in marine and non-marine extinction episodes suggest a common cause’. Note: this is a follow-up to a 2015 study with the same lead author, also featured at the Talkshop.
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Mass extinctions of land-dwelling animals—including amphibians, reptiles, mammals, and birds—follow a cycle of about 27 million years, coinciding with previously reported mass extinctions of ocean life, according to a new analysis published in the journal Historical Biology.

The study also finds that these mass extinctions align with major asteroid impacts and devastating volcanic outpourings of lava called flood-basalt eruptions—providing potential causes for why the extinctions occurred, reports

“It seems that large-body impacts and the pulses of internal Earth activity that create flood-basalt volcanism may be marching to the same 27-million-year drumbeat as the extinctions, perhaps paced by our orbit in the Galaxy,” said Michael Rampino, a professor in New York University’s Department of Biology and the study’s lead author.

Sixty-six million years ago, 70 percent of all species on land and in the seas, including the dinosaurs, suddenly went extinct, in the disastrous aftermath of the collision of a large asteroid or comet with the Earth.

Subsequently, paleontologists discovered that such mass extinctions of marine life, in which up to 90 percent of species disappeared, were not random events, but seemed to come in a 26-million-year cycle.

In their Historical Biology study, Rampino and co-authors Ken Caldeira of the Carnegie Institution for Science and Yuhong Zhu of NYU’s Center for Data Science, examined the record of mass extinctions of land-dwelling animals and concluded that they coincided with the extinctions of ocean life.

They also performed new statistical analyses of the extinctions of land species and demonstrated that those events followed a similar cycle of about 27.5 million years.

What could be causing the periodic mass extinctions on land and in the seas? Mass extinctions are not the only events occurring in cycles: the ages of impact craters—created by asteroids and comets crashing to the Earth’s surface—also follow a cycle aligning with the extinction cycle.

Astrophysicists hypothesize that periodic comet showers occur in the Solar System every 26 to 30 million years, producing cyclical impacts and resulting in periodic mass extinctions.

The Sun and planets cycle through the crowded mid-plane of the Milky Way Galaxy about every 30 million years. During those times, comet showers are possible, leading to large impacts on the Earth. The impacts can create conditions that would stress and potentially kill off land and marine life, including widespread dark and cold, wildfires, acid rain, and ozone depletion.

Full article here.

  1. tallbloke says:

    The next one is due on Jan 1st, because Brexit.

  2. tallbloke says:

    Remembering Svensmark’s important contribution to some of the cosmological connections to mass extinction events.

  3. tom0mason says:

    So many times scientists and the press like to highlight the ‘mass extinctions’ but pay scant regard for the almost continual incremental loss of (and the gain of new) flora and fauna that has happened, and is continuing to happen. But the focus is always on the events that have ‘star’ appeal like these unusual ‘mass extinctions’ and try to imaginatively couple them to current conditions. As far as I can see there is very little evidence that such catastrophic ‘mass extinctions’ will happen anytime soon.

    All this attention to sudden ‘mass extinctions’ seems to give the impression that all levels of extinction are strange and unusual when in fact it is quite the normal. Youngsters, and those of the eco-green persuasion, seem to be particularly ignorant of how nature works, and often believes that any extinction is caused by humans. Darwin’s ideas seems to be absent from so many peoples knowledge. Extinctions are the consequence of life on this planet. Life, as natural biology that continuously evolves to best fit this planet’s ever changing conditions. As far as I understand it, more than 99.9999% of all lifeforms that have ever lived on Earth are now extinct.

  4. stpaulchuck says:

    what’s the cycle length of the solar system passing through the plane of the galactic disc? Isn’t that around 27 million years? or is that span off a bit?

    from Universe Today: “…They calculated that we pass through the plane every 35 to 40 million years…. According to the number and age of craters on Earth, we seem to suffer increased impacts every 36 million years…”

    askin’ for a friend [*grin*]

  5. oldbrew says:

    Chuck – ‘You can think of the sun’s motion as being more like a horse going up and down on a carousel. We pass through the plane of the galaxy roughly every 30 million years. Currently we’re headed up out of the disk and are perched approximately 70 light-years above the plane of the galaxy.’
    – – –
    Next question: how long does each ‘pass’ take?

  6. Dodgy Geezer says:

    If you hit a geologically active planet with a large object like an asteroid, you are going to get big basalt flows. All the tectonic plates will be disturbed and leak at their edges.

    So a large impact and volcanic activity are always going to be correlated….

  7. Dodgy Geezer says:

    Brexit and racism and Global Warming – Oh Dear!

  8. oldbrew says:

    Wikipedia claim:
    The Holocene extinction, otherwise referred to as the sixth mass extinction or Anthropocene extinction, is an ongoing extinction event of species during the present Holocene epoch (with the more recent time sometimes called Anthropocene) as a result of human activity.

    No need to wait for the solar system to be disturbed by the galactic orbit 🙄

  9. oldmanK says:

    Re mass extinctions some may find this interesting pg 145 “THOUGHTS ON THE K-TEVENT”

    Click to access NCGTJV7N3%20-%20Ric.pdf

  10. Paul Vaughan says:

    recall shaviv (work with veizer) on 26 million — the sight of a classic story

    mods: check filter on SCL thread (dceptshhun busted …again with methods parameter lock $0[]well)

  11. Graeme No.3 says:

    This idea has been around for 30 years or more. I have one version (sceptical) in a book printed 1993.
    The dates given 249, 211, 191, 175, 160, 137, 125, 91, 65, 36, 14 with the proviso that they could be 5 million out in either direction.
    Firstly these ignore the end Ordovician extinction, the Devonian and Carboniferous changes in life (usually ascribed to ice ages).
    The end Permian is now dated to 252 and the ‘end’ Triassic at 220 unless the 191 figure for the start of the Jurassic applies. As far as I know the 175, 160 and 137 events don’t come under the heading of mass extinctions when compared with those in the Triassic (nor what was to come). Passing over the next 2 we get the “grand” one (actually the third worst) with the end of the dinosaurs. The final one (14) must refer to the Extinction of the Megafauna but this wasn’t a distinct event. The end in Australia was much sooner, possibly between 25 and 40 million y.a. whereas in north America it now appears to have been 11-12 million y.a.
    So the interval times appear more like 60, 80, 50, 41, 20, 16, 23, 12, 34, 26, 29, and whatever.
    I don’t see a repeating cycle there.

  12. Paul Vaughan says:

    shaviv and veizer had something clean – i don’t have time to dig for a link – but it was discussed at the talkshop and some talkshop page has all the links — may need to use the wayback machine if the sites are gone now

  13. oldbrew says:

    Gabfest: Putting down the heretics Soon, Balliunas, Shaviv, Veizer
    Posted: March 14, 2013 by tallbloke

  14. Paul Vaughan says:

    OB: that is definitely not the right link
    maybe search “26 million” “shaviv” “galactic arms” & maybe “bivalves” – something like that

  15. oldbrew says:

    PV: you can put this in the search engine and add a word or phrase.